Method of preparing N-(2-aminoalkyl)-2-aminoethoxylate ethane sulfonate

Abstract

The present invention relates to a synthesis method of thionate diamine by the reaction of alkali metal isethionate with diols to form alkali metal isethionate ethoxylate having the following structural formula: HO(CH.sub.2 CH.sub.2 O).sub.n CH.sub.2 CH.sub.2 SO.sub.3 A The above isethionate ethoxylate is then reacted with aliphatic diamine having a Carbon number of 2 to 6 to form a series of N-(2-aminoalkyl)-2-aminoethyoxylate ethane sulfonate having the following structure formula: H.sub.2 N--(CH.sub.2).sub.m --NH--(CH.sub.2 CH.sub.2 O).sub.n CH.sub.2 CH 2 SO 3 A wherein m=2-12 n=1-3 A=K or Na

What is claimed is: 
     
       1. A method of preparing N-(2-aminoalkyl)-2 aminoethoxylate ethane sulfonate comprising the step of reacting an alkali metal isethionate ethoxylate with an aliphatic diamine at a temperature within a range of 100 to 300 degrees C. to form a product having the following structural formula:   H.sub.2 N--(CH.sub.2).sub.m --NH--(CH.sub.2 CH.sub.2 O).sub.N CH.sub.2 CH.sub.2 SO.sub.3 A     wherein m=2-12, n=1-3 and A=K or Na.   
     
     
       2. The method as set forth in claim 1, wherein the step of reacting includes the step of adding an organic polar solvent. 
     
     
       3. A method of preparing an aqueous polyurethane dispersion, comprising the steps of: (a) reacting an alkali metal isethionate ethoxylate with an aliphatic diamine at a temperature within a range of 100 to 300 degrees C. to form a product having the following structural formula:   H.sub.2 N--(CH.sub.2).sub.m --NH--(CH.sub.2 CH.sub.2 O).sub.N CH.sub.2 CH.sub.2 SO.sub.3 A        wherein m=2-12, n=1-3 and A=K or Na;   (b) reacting a polymer selected from the group consisting of polyester and polyether polyol with a diisocyanate to form a prepolymer;   (c) adding a low boiling point organic solvent to the prepolymer of step (b);   (d) forming an aqueous solution of the product of step (a);   (e) adding the aqueous solution of step (d) to the organic solvent and prepolymer of step (c); and,   (f) removing the organic solvent.